Catalytic Ozonation of Emerging Pollutants in Water in the Presence of MCM-41 and Fe-MCM-41

The possibility that the modification of Mobil Composition of Matter No. 41 (MCM-41) by the incorporation of iron in its molecular structure and the loading of the support (iron substituted MCM-41; Fe-MCM-41) with active metals of manganese and cerium improve the removal of the representative organic pollutants (ibuprofen (IBU) and oxalic acid (OA)) in water in a catalytic ozonation process was investigated in this thesis. This study particularly addresses the preparation of modified catalysts, the role of pH and water matrices on the performance and stability of the catalysts, reaction pathways, and kinetics of the catalytic ozonation processes. As for preparation of modified catalysts, Fe-MCM-41 catalysts were effective for the ozonation of OA in water. The molecular framework of the prepared Fe-MCM-41 catalysts were stable up to 1wt% iron content and did not leach iron to the reaction solution during catalytic ozonation processes. High (94%) removal of OA was achieved in the presence of Fe-MCM-41 loaded with manganese and cerium oxides. However, the deposited metals on the Fe-MCM-41 support leached significantly (13-38% of initial concentration) during the processes. Regarding the reaction pathways, it was found out that the degradation of OA predominantly occurred by the reaction with hydroxyl radicals while IBU is mainly degraded by ozone molecule. The pH of reaction solution affected the activity and stability of catalysts for the removal of OA and IBU differently. For degradation of OA, Fe-MCM-41 presented similar catalytic activity in acidic pH conditions (55% removal of OA) with enhanced catalytic activity (14% additional OA removal) in basic pH conditions due to the generation of hydroxyl radicals. For degradation of IBU, the catalyst was very active (74-94% IBU removal) at the pH levels below the pHpzc of the catalyst. However, the catalyst was inactive at pH levels above pHpzc due to the permanent damage in its morphological structure. A modified kinetic model was derived basically by the mass balance of the consumed ozone and degraded total organic carbon. The results of the model were in good agreement with the literature, and it also confirmed the experimental observations

Appling real time RT-PCR for bluetongue virus detection in Iran

During 2009-10, real time RT-PCR and conventional RT-PCR techniques Used for detecting BTVs RNA in310 blood samples. For real time and gel based RT-PCR segment-1 and segment-10 selected as conservegenes to search any BTV strains. Using these methods, 58 (%18.7) and 14 (%4.5) positive samples weredetected among the clinically suspected sheep. Sensitivity of both molecular techniques evaluated by log-10 serial dilutions of BTV16 RNA, and determined 101.8 and 103.8 TCID50/ml in rRT-PCR and conventional RT-PCR respectively. This report confirmed rRT-PCR assay could detect weak BTV positive samples even at end stage of infection. In this study Virus isolation from selected positive samples failed by inoculation to embryonated chicken egg, Vero and KC cell

The Effect of Polymer on Triglyceride Microemulsion Formulation for Tertiary Oil Recovery

This paper presents the effect of polymer on the rheological properties of triglyceride microemulsions. Non-Newtonian shear thinning behavior of triglyceride microemulsions has been modeled satisfactorily using a power law. It was observed that the effects of surfactant and cosurfactant concentrations on the apparent viscosity are significant. However, the effect of salinity on the same viscosity is very trivial. Viscosities of the tested samples have shown a tendency to increase significantly with the addition of xanthan gum (high molecular weight exocellular polysaccharide). The increase is affected by the function of temperature and polymer concentrations, mainly influencing the terminal relaxation time of the solutions. This way, the optimum polymer concentration, 1500 ppm, was obtained on the basis of the performance of the optimum thickened triglyceride microemulsion in tertiary oil recovery at various temperatures and polymer concentrations

Correlations between interfacial tension and cumulative tertiary oil recovery in a triglyceride microemulsion flooding

This paper presents measurements of interfacial tension (IFT) and tertiary oil recovery (TOR) of triglyceride microemulsion flooding over a wide range of aqueous phase compositions. Based on 160 experimental data sets, two empirical correlations were established. Both the power-law and logarithmic models were validated statistically. Power-law and logarithmic models are predicted to perform best at ultralow IFT range (2 mN/m), respectively. The valid models indicate that IFT is the sole parameter affecting the cumulative TOR in a triglyceride microemulsion flooding. This phenomenon, however, does not apply in hydrocarbon-based microemulsions

Pre-prepared Microemulsion Flooding in Enhanced Oil Recovery: A Review

It is evident that one of the important applications of microemulsions is in enhanced oil recovery (EOR) process due to its unique properties such as ultra-low interfacial tension. The injection of microemulsion slug reduces the interfacial tension between the crude oil and reservoir brine, which leads to mobilization of substantial fraction of residual oil. In general microemulsion flooding is classified into two distinct categories, pre-prepared and in situ prepared, depending on its preparation method. The authors present a detailed discussion of microemulsion preparation and summarizes major articles on pre-prepared microemulsion flooding in EOR processes. Their review opens new horizons for the future researches on pre-prepared microemulsion flooding in EOR processes by organizing the literature data and comparing them

In Situ Prepared Microemulsion-polymer Flooding in Enhanced Oil Recovery—A Review

Microemulsion could be formed in situ through simultaneous injection of surfactant, cosurfactant, and brine into the reservoir. The formed microemulsion is expected to propagate toward the production well and along its way sweep significant amounts of the remaining hydrocarbon in the reservoir. There are numerous reports on in situ prepared microemulsion flooding in the literature. The interest in in situ prepared microemulsion flooding research activities is expected to increase tremendously in the near future because of its high potential in maximizing hydrocarbon recovery in enhanced oil recovery activities. The authors summarize major articles relevant to in situ prepared microemulsion flooding with application of various polymers in the flooding. They also discuss critically and extensively the effect and function of polymers and their role in the microemulsion flooding. This review opens new horizons for future research on in situ prepared microemulsion-polymer flooding in enhanced oil recovery processes by systematically organizing and comparing data in the literature. The data and information presented would be very useful to researchers conducting work related to enhanced oil recovery with microemulsion polymer flooding